Need more traction!

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leeparkes
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Post Mon Nov 14, 2011 7:18 pm

When i floor it from say 2k (in 2nd) its just lighting the rears up and its doing my head in. :(
What can i do to get more traction and get the power down?

Rear end spec is...

H&R cupkit springs & shocks, 40mm drop.
All new Lemforder bushes with void fillers in the subframe.
Standard 325i ARB with new drop links.
Dunlop SP Sport 205/50/15, also tried a few other brands including Toyo's, ive even had them down to 20 psi and its still struggling for grip. In the wet its another story. :mad:
3.64 LSD

What else can i do? softer springs/shocks, ive heard losing the ARB can help.

Thanks (in advance)
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
bmw9818
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Post Mon Nov 14, 2011 7:33 pm

im tryna figure this out as well, i got the same tyres 195/55/15s,

ive got a 316i and it spins through into 2nd in the wet, i floored it onto a busy roundabout and just ended up looking like a doofus spinning my wheels and not moving anywhere!

ive got no arb it doesnt make any difference btw
fuzzy
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Post Mon Nov 14, 2011 7:40 pm

live with it or control your right foot. imagine how hard it was with 330bhp and 300lbft. 8O
leeparkes
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Post Mon Nov 14, 2011 7:43 pm

fuzzy wrote:300lbft. 8O
Im not far off that, 285lbft. :)

Its annoying when you floor it off the line only to back off again to gain traction. :banghead:
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
jimbom30cab
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Post Mon Nov 14, 2011 7:45 pm

maybe something like this: http://autospeed.com/cms/title_Aftermar ... ticle.html

or sell me your entire M30 set up for say £50 and i've give you an M40 lump :mad: winkeye
fuzzy
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Post Mon Nov 14, 2011 7:47 pm

mine wasnt to bad in the dry, it was controllable but still able to get away quicker than most unless you did want to smoke them. in the wet it was useless though. dunlop sp's were my tyre of choice as well.
Kedge
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Post Mon Nov 14, 2011 7:48 pm

Rear beam with camber adjustment to get more tyre surface on the road!?
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Simon13
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Post Mon Nov 14, 2011 7:51 pm

wider rear wheels is the obvious one to me an 8j alpina or one of the 16x9 rims. Atleast you can say i need it!
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Post Mon Nov 14, 2011 7:51 pm

Lose the heavy right boot..
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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e30topless
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Post Mon Nov 14, 2011 8:01 pm

show off :wink:

your going to make the diffin crew jelous :D
E30BeemerLad
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Post Mon Nov 14, 2011 8:08 pm

I think this is ultimately just going to boil down to your right foot mate. Feed the power in rather than just snap the throttle wide open.

Or a few bags of cement in the boot.
Rav335uk
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Post Mon Nov 14, 2011 8:14 pm

Lee, you want to try some 225's on the rears???? winkeye
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Post Mon Nov 14, 2011 9:05 pm

You can go too wide and end up with less grip, the bigger the contact patch the less pressure on the road surface.

Getting the tyre closer to square against the road is a good start, loads of neg camber and lowered rear end just works against traction
penton08
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Post Mon Nov 14, 2011 9:05 pm

I run 235's on the rear and still struggle with traction. Softly, softly on the loud pedal is the only way.
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Post Mon Nov 14, 2011 9:38 pm

That's why I changed my diff lee. Try a 3:46 slipper.

You can light it up if you want but get a lot more traction over all.
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Post Mon Nov 14, 2011 11:45 pm

225's are the way forward. I dont rate Dunlop SP's either.
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leeparkes
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Post Tue Nov 15, 2011 4:27 pm

Thanks for all the replies lads, looks like a search for a new set of rims then. :)

@ Pento, do you have any scrubbing with 235's, whats the widest tyre you can get on an E30 without major work? (my arches are already rolled flat)
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
Jhonno
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Post Tue Nov 15, 2011 4:32 pm

215 was ok with my S50.. Hankook RS'2s..
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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cee
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Post Tue Nov 15, 2011 4:36 pm

Get a chubby girlfriend :cool:
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leeparkes
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Post Tue Nov 15, 2011 4:38 pm

Ive got a chubby engine, i dont want to add more weight to it! :mad: :)
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
penton08
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Post Tue Nov 15, 2011 6:00 pm

My arches are as near enough standard with 235/40/17's on 9j rims, it does not rub but it is pushing the limits of what will fit and the offset will need to be spot on.
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Funnybear
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Post Tue Nov 15, 2011 6:05 pm

As Scotty would say to the Captain . . . . Ye canna change the laws of fizzix. Cappin'.

Basic e30 facts (Just you can tell frag me down for telling you to suck eggs) Front engine. Rear wheel drive. Big on power, low in weight.

Wider rubber will help a certain degree, but without a sizable mass to press them into gods given black stuff you could have F1 tyres on the back, you still wouldn't have any grip. F1 cars are only grippy with active downforce, ergo . . . mass to push them into the track.

So whilst I'm sure you could find something to help a bit in your quest for grip you will hit a limit.

Suspension geometry might, again, help a bit. But as you are transfering energy into the rear dampers during acceleration (Pushing the rear wheels into the tarmac, generating a 'mass' effect, see above) the actually suspension setup could be letting you down there too. If you have alot of camber induced from either dropped or stiffened suspension then any more compression of the suspension components (unless you have an uber adjustable setup) will only induce more camber. Having the rear end as soft and compliant as possible (along with soft rubber) would help a bit, but ultimately would not make for a good handling car. High acceleration cars are often set up with 'positive' camber so that when the car accelerates the suspension compress's to make the tyres present as much rubber as possible to the road surface. Makes them a bitch to steer though.

Every and any car gives something up to make it good at something else. Want to do a sub 10 quarter, you need special rubber, engines and multi-stage acceleration control and rear weight bias, but don't go around a corner. If you do want to go around a corner, you need a 50/50 weight distribution, well setup suspension, good grip and an economical way to apply power.

Top speed equals less weight, less acceleration and less grip for windy stuff.

You immaculate e30 is also a compromise. Do you wish to go around corners, or do you wish to accelerate up to them, scare yourself shitless trying to slow down for them and wondering whether you'll manage to get out the other side of them. Cuz it sounds like you've reached a point of decision.

If you try and put more power through the back and want a perfect response then you'll have to remodel the rear suspension geometry and be prepared to make sacrifices in other areas.

Or, modulate the power input. Even Scotty has limits you know. He canna give ye any moar!
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Post Tue Nov 15, 2011 6:15 pm

I'd go for -25mm rear springs to get the camber more sensible and 55 profile rears to give the rear tyres more chance to deform to the road surface. (I run F205/50 R205/55)

Then I'd fit LPG. A great big tank in the boot does wonders for traction whilst reducing power a little, problem solved.
I said:

Can anyone suggest how to test if the boot lights are staying on with the boot shut?

e30topless said:

lock the wife in there
Kedge
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Post Tue Nov 15, 2011 6:20 pm

I still don't understand why you are not considering an adjustable rear beam and going for wider tyres. :?
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Post Tue Nov 15, 2011 6:47 pm

Wider tyres do not equal more grip. The area of contact does not figure in the equations for friction (=grip). The reason for wider tyres is to put the power down without exceeding the maximum power per square centimetre that the tyres in question can transmit.
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Post Tue Nov 15, 2011 6:59 pm

Get a big sub in the back to balance out the extra weight in the front winkeye

My JL13W7 with amps and box, puts about 80kg over the rear wheels and makes a noticeable difference!!!
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Post Tue Nov 15, 2011 7:08 pm

I'll say it again. 225's. No more now less.
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Funnybear
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Post Tue Nov 15, 2011 8:57 pm

FIZZIX!!!!
m_jermyn
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Post Tue Nov 15, 2011 11:18 pm

Lee you need these mate.


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Post Thu Nov 17, 2011 11:53 pm

e301988325i wrote:Then I'd fit LPG. A great big tank in the boot does wonders for traction whilst reducing power a little, problem solved.
Works for me! :) Mine being a touring with an LPG tank in the boot has plenty of rear grip.

Try running a full tank of fuel with something heavy in the boot and you'll be close.

The downside... 1400kg in road trim 8O
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leeparkes
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Post Fri Nov 18, 2011 12:03 am

Been looking at 16 x 8's & 9's but the ones i like are around 2 bags :cry:
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
Rav335uk
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Post Fri Nov 18, 2011 12:27 am

There was a set of RS's 16x8/9 in 4x100 for £1500 over on ED38 Lee yesterday. winkeye
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leeparkes
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Post Fri Nov 18, 2011 4:45 pm

Have you seen them? need a refurb. :eek: 15" centres too.

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http://www.edition38.com/forums/index.p ... pic=419338

Are those the ones?


Some redrilled ones here, right on your doorstep too. :D

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http://www.edition38.com/forums/index.p ... pic=417511


Id love a set of RS' but they would hardly ever be on the car, id be shit scared some coont would rob them. :)

Ive set a budget of around £700.
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
leeparkes
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Post Fri Nov 18, 2011 5:14 pm

These folks are on my doorstep. winkeye

http://www.imagewheels.co.uk/index.html

I hear Bootyman gets discount too. :)
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
Kedge
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Post Fri Nov 18, 2011 5:23 pm

leeparkes wrote:These folks are on my doorstep. winkeye

http://www.imagewheels.co.uk/index.html

I hear Bootyman gets discount too. :)
He certainlly used to, can't remember how much though.

I kept looking at their wheels but then what i would want wouldn't be that much less than something like a set of BBS splits, and if there came a time you wanted to sell there's only one set that would have a really strong resale value.
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